The known constructions of flying valves for plunger lift contain a tubular body and a detachable element, as a rule, in the form of a steel ball (inventor's certificates SU 63138, SU 171351, SU 596710, SU 791939, SU 802525, and U.S. Pat. No. 2,074,012, U.S. Pat. No. 3,090,316, U.S. Pat. No. 6,209,637). All above devices satisfactorily work in small-diameter wells when diameter and hence the mass of the body and detachable element of flying valves are relatively small. With the increase of well diameters and the mass of steel balls the use of flying valves becomes seriously complicated or even impossible due to jump of shock loads resulting in deformation of tubes in wells, damage of equipment and even destruction of steel balls.